Hammer-drill.



PATENTED NOV. 5, 1907.

A. E. JOHNSON. HAMMER DRILL.

APPLIUATON FILED IEB. 23. 1906.

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' UNITED STAT *PATENT OFFIOE.

ALFRED JOHNSON, or DENVER, COLORADO, llssIoNOa 'ro THE una Roon DRILLMANU FAoTURINe Conni-Nr, or DENVER, COLORADO.

Hmm-DRILL.

Specification of Letters Patent.

Patented Nov. 5, 1907.

Application filed Ysbrnary 2 3' 1306. Serial No. 302,3?3.

Toall 'whom i: may concern:

le 'it known that L ALFRED E.- J Ons-sox". a citizen litho UnitedStates, residing at the city and county r. Denn-r, and State ofColorado,l have invented certain new and useful4 Improvements in Hammer#Drills; and I do declare the following tolbea full, clear, and exactdescription of the invention, stichw-as will enable others skilled inthe art to which it appertairrs to ineke and use the same, referencebeing had to the accompanying drawings', and to the letters and figuressi reference marked there-tri, which form'a part o1 this specicatioir.

lily invention relates to improvements m'hammer drills or tools in whichthe reciprocating part or hamnier is. not. directly connected with thedrill bit or Y tool the said part being actuated by air or other' suit-,the rear extremity oi the conduit is journaled. l The motive iuiti foroperatingthe tool is introduced to the hollow conduit at its abutmentextremity. My presant inventlfn relates to the particular constructionof the rear extremity o: the hollow conduit and the sleeve et theal'utmcot'nto which this rear extremity protrudes. .tu my presentimprovement this rear ex'- tremity with the hollow condon constats oaspindle memhex-demchablv connected with the body of conduit md' having apassage communicating therewith. This passalze also communicates withports formed in the. spindle which in turn. communicate a chamber ofthe-abutment, when'the latter is moved forwardly on the spindle foroperating purposes. The rear extremity oi the spindle member of ille conduit has 'an enlarged bead around 'which the motivev iluid is allowed'tocirculate in the abutment chamber. The torward extremity 'ci this headconisisot' a beveled lace which when the abutment is at its rearwardlimit ol movement` engages a .shoulder oi the abut ment sleeve. leavinga spate 1neto/een the beveled face i the s riimiw.` .uca-:l :and theangle-fortified with-the The induction pei-t othe extrem-ity d ficulderthe sleeve. sleeve communicates with the to the chamber of the sleeve,4thus allowing the motive iluid to enter the space in thesleevelbetwecil the beveled headof the spindle and the shoulder of thesleeve, when the'abntmenr is at its rearward limit' of movement. Byvirtue of this'construction, the operator in moving the abutment forwardto begin the r.operation oi the device, does not have to push againstthe entire pressure acting against the rear end o the abutment proper,since the action ofthe lluid on the shoulder of the abutment reduces theeffective pres- 'sure area. to4 a considerable extent. This is animprovernent over the-original construction set iortll inthe saidpatent.

Having briefly outlined'my' improved construction,4 I will proceedtodescribe the same in dctailfreer- :ence .being made to theaccompanying drawing. in

which isillustrated an embodiment thereof.

' In the drawings, Figure l is a longitudinal section taken through ahammer drill equipped with my` improvements. Fig. 2 is a ragmcr-.f-iryview oi the same showing the parts on a larger .cale the relativeposition oi the abutment and hollov; crank being the l same asin Fig. l,Flg. 3 is a view .similar to Fig. 2

but showing the abutment and hollow crank in different relativepositions.

The same reference characters indicate the same parts in all the views.

'Let the numeral 5 designate the body oi the tool, 6 l the drill bit orsteel arranged to be act-ed on by the hammer 7 which as shown in thisinstance acts directly on a tappet 4 interposed between the hammer anddrill bit. This hammer may consist of any deeircd form oi reciprocatingstriker. In this instance its general shape is cylindrical and it ismounted to reciprocate in a chamber of corresponding shape formed in thebody or' casing 5 of the tool. in this instance the hammer is adapted tomove through av valve sleeve A whose extremities are providedI withpressure surfaces of different areas.

suitably connected with the near extremity'of the cylinder 5 is thehollow crank 8. In this instance they forward extremity of this crank isconnected with the cylindarbya sleeve 9 formed integral with the hollowcrank but split a short distance from its ex# tremity as shown at 10 togive the necessary clamping capacity. Through this split portion of thesleeve is passed a bolt 12 whereby the crank is securely fastenedto thebody 5 of the tooL To facilitate Ythe securing of iw two parte together,the sleeve together with the rearward xtremity of the body of 'che toolis threaded. .im .Lhexhr'eldod connection imode the parte are Vam 2 po'z'onvsv 'position at any desired distance from said center accordingto the desired leverage. The part B is fixedly:

connected with a hollow spindleY 13. In lthis instance the forwardextremity of the spindle 4or that farther to the right in the drawing isthreaded into the 'extremity `.B of the crank. Thisextremity of thecrank has a chamber 14 which the hollow spindle enters and with whichthe hollow of the. spindle communicates 1 by means of ports l5. The rearextremity of the spindle part 13 of the crank', enters a sleeve 16'which is pro'- vided with a suitable packing' l' to form a fluid tightjoint between-the sleeve and the'spindle in orderto prevent leakage ofthe operating fluid. The rear ex.- tremi'ty of the part 13 has anenlarged part or head 18. .This head isadapt'ed to slide freely in a'chamber 19 formed in therear portion of the sleeve 16. VThe rearextremity of the sleeve iis closed4 by the 'abutment proper 20 which hasa threaded lug 21Awhich enters the interiorly threaded rear portion ofthe sleeve. The ports 15 of the part 13 communicate at their [innerextremities with a longitudinal passage22 formed in the spindle, thelatter being also provided near its rear extremity with ports 23 whichcommunicate with the sleeve chamber 19 when the parts aref in therelative position shown in Fig. 3.

' located inclined or beveled face 18* which engages the corner of anabrupt shoulder 26 formed on the sleeve, thus leaving a space 27betweenthe said face and the shoulder angle of the sleeve which spacereceives the y operating fluid when the abutment is at its rearwardlimit of movement (see Figs. 1 and2). The head 18 does not tit tightlywithin the chamber 19 of thesleeve, but the parts are so formed as toallow the operating fluid to pass the said' head and occupy apositionbe-- tween the abutment and the spindle head whereby it furnis a cushionand Arelieves the operator from Ythe annoyance due tothe vibration oftools of this character.

that the crank and abutment are in the rel-.nivo position shown in Fig.1, if fluid be introduced at the port 24, it will pass to the chamber 19and also 'to the space between the face: 13A of the spindle and' theadjacent angle'o the sleeve. when the parts are in this lmsitou'no fluidprrsseslln'ouglr the hollow lcmnlt to rho lool, since the ].\orls2.- arelocated forward chamber 14 o the hollow-crank and thence through v theangular passage 28 of the crank. to an annular chamber 29 formed in theclamping sleeve -9. From this chamber 29, the fluid passes through ports30 'formed in a detachable part 31 of the cylinder, into a circum- .70ferential groove 32 formed on the inside of the part 3l and surroundingthe outer surface of the sleeve valve A. Now assuming that the hammer isat its forward limit of movement as shown in Fig. 1, and-that the Asleeve valve is at im rearward limit of-movement, the operating fluidwhich has driven the hammer for ward hasrexhaused through ports 33formed in the valve, into a circumferential groove 34 formed in the'member 3l, the exhaust passing thence through rearwardly-extendingopenings 35 (indicated by dotted 80 i lines in Fig. l) to thc exhaustchamber 36 andthence' A to the atmosphere through a paagel'. A smallpart of the operating fluid,howeve,.cnters a transverse pesage-38 formedin a member 39 and passes thence through a duct Ai0 formed in aforwardly-extending 85 stern 4l of the member-.39, passing thenceoutwardly through ducts 42 iutoan annular space 43 formed in the rearextremity of the hammer and communicating by means of ducts 44 withlongitudinal grooves 45 formed in the outer wall of the hammer andcommunieating with the forward cxtermity. of the'sleeve valve.

lt is the action of this fluid which has imparted the rearward movementto'the valve or caused it to occupy the position shown in Fig. 1. Thisfluid also flows through a central passage 47 ol' the hammer and escapes95 therefrom through pasages 4S lo a chamber 4'.` where the iluid actsto rclum the hununcr to its rearward limit of movement. A ftcr thehammer during this rearward movement passes the exhaust ports 33 of thcvalve, the motive fluid cushions between the rear ex- 100 tremity ofthe-hammer and the 'chamber in the rear of the exhaust ports and theresulting uid prcure acting on the relatively small surface area of theroar extremity of the valve, imparts the forward movement to the valveand bringsv its ports 33 into communication 105 with the interiorcircumferential groove 32 of the member 31, allowing the motive fluid topam to the hamrncr chamber, the ports `33 of thevalve "hich haveheretofore been designated as exhaust ports, new becoming induction,ports. The-Huid cushion in the rear of 'the 110 hammer as it iscompleting its rem-ward stroke, reacts i on the hammer dnd Aimpartsthereto a forward movement sulicient to bring its reanextremity. forwardof the valve ports 33 whenA the valve is at its forward limitofmovement, thus allowing the motive lluid to enter behind the hammer andact'thcreou to impart its' forward or working stroke. .i

In the construction shown, the motive fluid forward of the hammer duringapart of the lutters forward strike, escapes into a circumferentialgromo 50 ornwd 120 in the inner wall of the cylinder and pass-s thencethrough ducts 5l, 52 and ports 53, to the drill steel or bit which it isassumed is provided with a piange for delivering the iluid to the Ainnerextremity of thc drill hole `for the purpose u( cleaning out the latter.

As nothing is claimed. on thc specific consrructitm of hanuncr or'striking mechanism in this application l the said mechanism and itsprinciple of operation will not he further set. forth iu detail.

'As soon as the operator ceases to press on the shut 130 thil spindlennd its htx-td within the abutment chamber b0- im.r ul :t size to allowthc motive ihthl in )mss therenrnnnd fm' tht` pnrlmsc svt furth.

ln :t hnmlnvr drill. tin` conthlnnttnn with the body uf thoitmtt'tuntnt. of nn ztlmtnwnt. :t hollow nwmht-r connectA ing tlnlmtlyol' the tutti with thc nlmttncnt. the abutment oxtrttnity uf thu crunkconsisting ui' n hollow spindle dctnrlmhly runtxtrtttl with tht: wildhnllnw tnvtnlxr tutti haring :in vnlnrgvd lit-ntl lut-:ttul within :tclnnnhcr t'nrxnt-t. in titt- :thntmvnt the spintlln :intl its htfttllwing.: frcc to slitlc in th:` snitl ('hzttnlwr .thu :mid hcntl livingprovitlvd with n llovlutl t'urwnrtl int'v :tml the :thntmt-nt with :tshnnlth-r lnrzttvtl apposito tht) sititl faire wht-n tht: :tbnlntent intits watt-viril limit nl' murcmcnt. tht* :thntntcnt beim: prm'ldtwlwitl-l :t tttntn'ttlntt intlnutinn puri; cntnnntnivning with tln-:xhntntt-nt t-hnmlwr.

ln tt-stimnny wiwi-wf 1 nttix tn v signatur in presence of two wilntmsw.

